盐酸小檗碱抑制结肠癌细胞环氧化酶-2/钙离子途径

目的探讨盐酸小檗碱对结肠癌细胞系生长、增殖的作用及环氧化酶2/钙离子途径的影响,为阐明盐酸小檗碱作为一种新的结肠癌化学治疗药物进行理论上的准备。方法0.1、0.3、3.0、30.0μmol·L-1的盐酸小檗碱加入到HT29结肠癌细胞系培养液中。MTT法检测细胞的生长和增殖,RTPCR法检测环氧化酶2mRNA,免疫细胞化学法检测环氧化酶2蛋白质表达,ELISA法检测前列腺素E2的含量,免疫荧光分光光度法检测细胞内钙离子浓度([Ca2+]i)。结果盐酸小檗碱在浓度大于0.3μmol·L-1时则有明显的量效关系抑制细胞的生长、增殖;在浓度大于0.3μmol·L-1时对环氧化酶2mRNA水平和蛋白的表达有明显的抑制作用;对前列腺素E2的生成有抑制作用,可以降低细胞内钙离子浓度。结论盐酸小檗碱通过抑制细胞内钙离子浓度进而通过某些途径抑制COX2在mRNA水平和蛋白质水平的表达,同时也抑制COX2活性进而抑制前列腺素E2的生成,这可能是其抑制HT29细胞生长和增殖的机制之一。

The inhibitory effect of berberine on cyclooxygenase-2/Ca2+ pathway in human colon cell line

Aim To investigate the effect of berberine on the proliferation of human colon cancer cell line and cyclooxygenase-2(COX-2)/ Ca2+ pathway. Methods 0.1,0.3,3.0 and 30.0 μmol·L-1 of berberine were added into the cell culture medium. MTT method was used to observe the effect of berberine on the growth and proliferation of colon cells. RT-PCR method was used to test COX-2 mRNA. Immunocytochemical method was used to test the expression of COX-2 protein. ELISA method was used to test the concentration of prostaglandin E_2(PGE_2). Immunofluorescence method was used to detect [Ca2+]_i. Results When the concentration of berberine was higher than 0.3 μmol·L-1,it inhibited the growth and proliferation of colon cancer cells in a dose-dependent manner. When the concentration of berberine was higher than 0.3 μmol·L-1,it inhibited the COX-2 mRNA and protein level. Berberine decreased the concentration of prostaglandin E_2 in the culture medium. Conclusions Berberine can inhibit [Ca2+]_i and thus inhibit COX-2 mRNA level and protein expression. It can also inhibit COX-2 activity and the synthesis of PGE_2. This may be one of the mechanisms of berberine inhibition against the growth and proliferation of HT-29 human colon cell line.